Arsenal handed injury blow with Shkodran Mustafi ruled out 'for a long time' with torn hamstring

Defender Mustafi was forced off after just 36 minutes in Kaiserslautern with what coach Joachim Low described afterwards as a "serious" muscle injury

Shkodran Mustafi looks set for a lengthy spell on the sidelines (Bongarts)

Arsenal have been dealt a significant blow after Shkodran Mustafi looks set for an extended spell on the sidelines after limping out of Germany's 5-1 World Cup qualifying win over Azerbaijan.

Defender Mustafi was forced off after just 36 minutes in Kaiserslautern after he pulled up suddenly as he attempted to follow Ramil Sheydaev, who went on to score Azerbaijan's goal.

Coach Joachim Low later described Mustafi's knock as a "serious" muscle injury.

"I think Mustafi has a muscle tear," he said. "It looks a bit more serious. A hamstring injury to a muscle tear, we have to wait for the exact diagnosis, but he'll probably be out for a long time."

Mustafi has made five appearances for Arsenal in the Premier League so far this season.

Schalke's Leon Goretzka scored twice, including a brilliant backheel, with Sandro Wagner, Antonio Rudiger and Emre Can also netting.

And midfielder Goretzka is now targeting a starring role at next summer's Wormd Cup: "I think we were very consistent throughout the qualifiers and we deserved to qualify with a perfect record.

"I was happy with my role in the Confederations Cup, but now I think it's time to play a big role in a big tournament like the World Cup."